.gitignore for umbraco, including user-specific data - asp.net-mvc

Question

Using visual studio and the Umbraco NuGet package, I'd like to setup a basic Umbraco installation containing:
some umbraco packages, such as Optimus
some individual document types
This should be wrapped by a git repo.
Where possible, I'd like to exclude generated/compiled files by adding the affected paths/file extensions to the .gitignore file.
I started off using the official umbraco .gitignore which has the following entries:
# Note: VisualStudio gitignore rules may also be relevant
# Umbraco
# Ignore unimportant folders generated by Umbraco
**/App_Data/Logs/
**/App_Data/[Pp]review/
**/App_Data/TEMP/
**/App_Data/NuGetBackup/
# Ignore Umbraco content cache file
**/App_Data/umbraco.config
# Don't ignore Umbraco packages (VisualStudio.gitignore mistakes this for a NuGet packages folder)
# Make sure to include details from VisualStudio.gitignore BEFORE this
!**/App_Data/[Pp]ackages/
!**/[Uu]mbraco/[Dd]eveloper/[Pp]ackages
# ImageProcessor DiskCache
**/App_Data/cache/
However, this would not include the database nor installed packages, so I also added the following entries*:
!**/Aa]pp_[Dd]ata/packages
!**/Aa]pp_[Dd]ata/Umbraco.sdf
!**/[Bb]in/*.pdb
!**/[Uu]mbraco/[Cc]onfig
see discussion here
Using this configuration, ReSharper would list 3 errors which occur in the global web.config file:
my-umbraco-project\Web.config:87 Cannot resolve symbol 'Providers'
my-umbraco-project\Web.config:87 Cannot resolve symbol 'DefaultSessionStateProvider'
my-umbraco-project\Web.config:87 Invalid module qualification: Failed to resolve assembly System.Web.Providers
However, I can compile, log-in to my umbraco instance and even the pre-installed plugin would appear.
This basically leaves 2 questions:
What do I additionally have to include in order to fix the 3 errors?
Are there more compiled/generated files I could exclude?

Answer 1

So here's the .gitignore we use without any issues:
[Oo]bj/
[Bb]in/
.nuget/
.vs/
_ReSharper.*
packages/
artifacts/
*.user
*.suo
*.userprefs
*.dbmdl
*DS_Store
*.sln.ide
# Umbraco
# Ignore unimportant folders generated by Umbraco
**/App_Data/Logs/
**/App_Data/[Pp]review/
**/App_Data/TEMP/
**/App_Data/NuGetBackup/
# Ignore Umbraco content cache file
**/App_Data/umbraco.config
# Don't ignore Umbraco packages (VisualStudio.gitignore mistakes this for a NuGet packages folder)
# Make sure to include details from VisualStudio.gitignore BEFORE this
!**/App_Data/[Pp]ackages/
!**/[Uu]mbraco/[Dd]eveloper/[Pp]ackages
!*UmbracoModelsBuilder.user
# ImageProcessor DiskCache
**/App_Data/cache/